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In the middle of Europe, the Alps form a geographical and meteorological trap for atmospheric pollutants including volatile and semi-volatile organic compounds emitted in the surrounding lowlands. This is due to their barrier effects, high precipitation rates, and low ambient temperatures. Also the pollutants emitted in the cities inside the Alps spread in the region depending on orographic and meteorological conditions. Although a number of studies on the distribution and effect of pollutants in the Alps has been published, comprehensive information on potential hazards, and ways to improve this sensible environment are lacking. This opinion paper is the result of a discussion during the Winterseminar of the AlpsBioCluster project in Munich. It summarizes the current literature and presents some case studies on local pollution sources in the Alps, and the possibility of using biomonitoring techniques to assess critical pollution loads and distributions. [ABSTRACT FROM AUTHOR]

Four cores (ranging between ca. 9 and ca. 14 m in length) from Lago di Albano in Central Italy were studied for their ostracod content, as well as algal and bacterial pigments, CaCO3 and concentration of organic matter. Cores PALB 94 1E and PALB 94 1C from Site 1, located at the bottom of a steep slope at 70 m water depth, where oxygen concentration is below 6 mg l-1, spans the Holocene and the late Pleistocene until 28 kyr B.P. (calibrated age). The other cores, PALB 94 6A and PALB 94 6B taken at a depth of 30 m, where oxygen is 7--11 mg l-1, represent mainly Pleistocene deposits. Ostracod valves were found in the lowermost ca. 3 m of the sequence at Site 1, dated to ca. 28--24 kyr B.P., and throughout the sequence from Site 6 which represents the interval 23--17 kyr B.P. Candona neglecta is the dominant species in most of the levels at Site 1, whereas both C. neglecta and Cyclocypris sp. dominate during different biostratigraphic zones at Site 6. The influx of springs entering the lake at Site 1 was inferred on the basis of species of the genus Potamocypris and Ilyocypris bradyi present in the record. Wide fluctuations in species abundance and assemblages in both coring sites indicate lake-water level oscillations between 28 to 17 kyr B.P. In particular, a strong rise in water level of the order of 40 m occurred between 24 and 23 kyr B.P. Fluctuations in productivity, oxygen availability and water temperature at both sites were also reconstructed on the basis of the ostracod assemblages and the algal and bacterial pigment concentrations. The environmental reconstruction reached using ostracod remains and pigments was verified with other proxy records published elsewhere such as invertebrate remains, diatoms, magnetic properties, etc. A synthesis of climatic reconstructions for Central and Southern Italy for the late Full Glacial is attempted on the basis of previous studies on hydrology, lithostratigraphy and palynology. Sharp fluctuations in lake palaeoproductivity/palaeoclimate recorded by invertebrate and pigment remains at both sites from Lago di Albano might be related to similar events reported in North Atlantic Full-Glacial records from marine and ice cores. [ABSTRACT FROM AUTHOR]

A fine resolution study on fossil ostracods in late glacial sediments from Lago di Albano was performed within the framework of the European project PALICLAS. Four cores from two coring sites were analysed.At Site 1, located at 70 m depth, cores PALB94 1E and PALB94 1C werecollected, while cores PALB94 6A and PALB94 6B were collected at Site 6 at 30 m depth. The autoecology of the ostracod species, cluster analysis, PCA and CA ordination numerical analyses were performed in order to identify changes in environmental conditions within the sedimentary record. Three assemblages were recognized: (a) dominated by C.neglecta representing sublittoral environments, (b) dominated by C. neglecta accompanied by Potamocypris spp. related to spring influx and (c) dominated by Cyclocypris sp. associated with littoral and relatively warmer conditions.A reconstruction of lake water level, oxygen concentration near the bottom and lake productivity, based on ostracod autoecology and supported by fossil pigment data, was accomplished.Sharp fluctuations in water level and productivity seem to indicate climatic oscillations between ca 30 to ca 17 kyr BP. [ABSTRACT FROM AUTHOR]

This paper reports the results of biological analyses (pigments, diatoms, chrysophyte cysts, cladocerans, chironomids and ostracods) of aca. 14 m-long sediment core recovered from Lake Albano (Central Italy) in the course of the EU-funded project PALICLAS (PALaeoenvironmental analysis of Italian Crater Lake and Adriatic Sediments).A reconstruction of the environmental evolution and ecosystem response of Lake Albano during the last ca. 30 kyr was possible. Additional information on lake level oscillation is obtained from benthic and planktonic palaeocommunities. Several oscillations in the productivity and the level of the lake were detected in the oldest sediment layers (from ca.30 kyr BP to ca. 17 kyr BP), followed by a long (ca. 5 kyr BP) period of low productivity in which cold, holomictic conditions prevailed.A period of high biological activity and, probably, meromictic conditions during the early-mid Holocene was detected. A clear impact of human activities in the catchment was found at ca. 4 kyr BP in the form of increased erosion, associated with a decline in the abundance ofbiological remains. Further signs of human impact on the lake ecosystem are recorded during the Roman period. Although large-scale environmental changes (e.g. regional climate changes) caused many of the observed biological changes, human activities were important during themid-late Holocene. [ABSTRACT FROM AUTHOR]